Substituted cyclopentadienes, methods of manufacture and uses

Abstract

Tertiary alkyl substituted cyclopentadienes are prepared by reaction of cyclopentadiene with a stoichiometric excess of a tertiary alkyl halide under phase transfer conditions. The tertiary-alkyl substituted cyclopentadienes are useful as synthetic lubricants.

What is claimed is: 
     
       1. Tertiary alkyl substituted cyclopentadienes of the following formula: ##STR6## wherein R 1  is hydrogen or non-tertiary alkyl of 1 to 4 carbon atoms, R 2  is tertiary-alkyl of 4 to 12 carbon atoms, and a is 2 or 3, with the proviso that when R 1  is hydrogen, a is 3 and R 2  is attached to the cyclopentadiene ring through a tertiary carbon. 
     
     
       2. A compound according to claim 1 wherein R 1  is hydrogen and R 2  is tertiary-butyl. 
     
     
       3. Tertiary substituted cyclopentadiene of the following formula: ##STR7## wherein R 1  is hydrogen or alkyl of 1 to 4 carbon atoms, R 3  is straight or branch chained alkyl of 2 to 9 carbon atoms, and b is 1 to 4, provided that when R 1  is H, b is at least 2. 
     
     
       4. Cyclopentadienes of claim 3 wherein b is 1 to 3. 
     
     
       5. The cyclopentadiene of claim 3 wherein R 1  is 14 and b is 2 or 3. 
     
     
       6. A method for the preparation of an alkylated cyclopentadiene wherein the cyclopentadiene ring is alkylated by at least two tertiary-alkyl groups attached to the cyclopentadiene ring through a tertiary carbon, which comprises the reaction of cyclopentadiene with a stoichiometric excess of a saturated tertiary-alkyl halide, in the presence of a strong base catalyst and a phase transfer agent at an elevated temperature with vigorous agitation, and wherein the amount of said phase transfer agent is about 1 to 50 mole % of the amount of cyclopentadiene being reacted. 
     
     
       7. A method according to claim 6, wherein the reaction is carried out at an elevated temperature over a period of thirty minutes to three days and the phase transfer agent is a quaternary ammonium halide. 
     
     
       8. A method according to claim 6 wherein a molar excess of tertiary-alkyl halide of at least 3:1 is used in the reaction. 
     
     
       9. A method according to claim 6 wherein the tertiary=alkyl halide is t-butyl bromide. 
     
     
       10. A synthetic lubricating composition comprising a tertiary alkyl substituted cyclopentadiene of the following formula: ##STR8## wherein R 1  is hydrogen or an alkyl of 1 to 4 carbon atoms, R 2  is tertiary-alkyl of 4 to 10 carbon atoms, and a is 1 or 5, and is attached to the cyclopentadiene ring through a tertiary carbon, in combination with a lubricating additive, providing that the number of carbons in R 1  plus a times the number of carbons in R 2  ≧12. 
     
     
       11. A synthetic lubricating composition according to claim 10 which also contains from 0.01 to 40% by weight of a lubricating oil additive.